V → T ,R and V→V relaxation in DCl systems

Abstract

A laser‐fluorescence technique was used to measure the $\mathrm{V}\to \mathrm{T}$ ,R relaxation of DCl (ν = 1) by DCl, rare gases, and hydrogen isotopes, as well as the $\mathrm{V}\to \mathrm{V}$ relaxation of HCl, DCl, and CO by deuterium halides, first‐row diatomics, and some polyatomic molecules. The dependence of $\mathrm{V}\to \mathrm{V}$ probabilities on energy discrepancy qualitatively indicates the role of rotation in removing excess vibrational energy. Significant differences in the interaction potential between HX and various first‐row diatomics is also suggested. $\mathrm{HCl}{\mathrm{\to \hspace{0.17em}}}^{16}{\mathrm{O}}_2$ and ${}^{18}{\mathrm{O}}_2\hspace{0.17em}\mathrm{V}\to \mathrm{V}$ relaxation was measured and leads to an estimated probability for the multiquantum process, $\mathrm{HCl}{\text{(ν=1)+\hspace{0.17em}}}^{18}{\mathrm{O}}_2\text{(ν=0)→}\mathrm{HCl}{\text{(ν=0)+\hspace{0.17em}}}^{18}{\mathrm{O}}_2\text{\hspace{0.17em}(ν=2)+Δ E=−30\hspace{0.17em}}{\mathrm{cm}}^{\text{−1}}$ .